Project financed by UEFISCDI, Ministry of National Education

 

Program PN III - P4 - Fundamental and Frontier Research

Project type : Exploratory Research Projects (PCE2016)

Project code: PN-III-P4-ID-PCE-2016-0208

Contract Number: 64/2017

Period: 2017-2019

PROJECT LEADER: Dr. ATTILA BENDE (Scientific Researcher I)

TITLE: Design of some spin-crossover supramolecular structures controlled by ultrashort laser pulses

ABSTRACT: The present project proposes to elaborate a detailed theoretical framework for laying out different supramolecular complexes with well-defined properties based on the spin crossover effects. To achieve this goal, the density functional theory (DFT) and its linear response time-dependent (TDDFT) version will be considered as the theoretical framework to describe different electronic excited states in "low" and "high" total spin configuration. In the first period of the project implementation, the validation of the used theoretical model will be carried out through the comparison with already existing experimental measurements. This investigation will be followed by a detailed description of the physical phenomena of the laser induced spin transition in organometallic complexes which mainly includes: theoretical characterization of the molecular electronic excited states; description of the radiation decay pathways and localization of the intersystem crossing points; calculation of the spin-orbit couplings. After the successful validation and development of the theoretical framework, several metal-ligand structures will be investigated in order to design metal-coordinated macrocycles with efficient spin transitions driven by the external laser field in controlled manner. Each case of metal-coordinated macrocycles will be characterized in detail and the most promising candidates will be selected for chemical synthesis. After the successful synthesis, the macrocycle compounds will be investigated using different spectroscopy techniques, like UV-Vis, transient absorption or Raman in order to characterize their spin crossover properties. Based on these analyses the most important feature of the spin crossover complexes, namely the ligand bond length variation driven by an external laser field in controlled manner, will be applied in case of sulfonated coordination polymer networks to build molecular materials with special properties.

Contact:

Donat Street, 67-103, Ro-400293

Cluj-Napoca, Romania

Phone: 0040-(0)264-584037 ext. 194

Fax: 0040-(0)264-420042

E-mail: bende@itim-cj.ro